Enabling the Ping finder and the feedback mechanism

You can discover neighboring connected devices using the feedback mechanism. Feedback enables the discovery process to learn about the existence of devices as a result of querying other devices. In order for feedback to work, the Ping finder must be enabled.

1. Click Seed.
2. Check that Use Ping Finder in Discovery is checked.
   The Ping finder is used to enable discovery to ping devices to verify existence and is used at various points in the discovery, including the following:

   • At the early stages to discover devices in the ping seed list and to perform ping sweeps of subnets.
   • Throughout the discovery to verify remote neighbors discovered as part of the feedback mechanism.
   • To identify the active interfaces on any subnets found.
3. Click Advanced.
   The Advanced tab contains a large number of configuration settings that the advanced user can set to work around unconventional network behavior.
4. In the Advanced Discovery Configuration section of the panel, check the setting for Enable Feedback Control.

   By default, feedback is set to Feedback only on Full, and this is the desired setting. This setting ensures that feedback is active when you are performing a full discovery, a discovery of your entire network. The entire network is made up of the managed areas that you defined using your discovery scopes.

   The other settings for Enable Feedback Control are as follows:

   No feedback

   This setting is useful when you want to strictly limit discovery to a predefined list of IP addresses, and you do not want the discovery process to discover any connected devices that are not in the predefined list. You will learn more about this setting when you set up your production discovery configuration.

   Feedback

   This setting switches on feedback for both full discovery and partial discovery. Partial discovery is a discovery of only a part of your network such as one or more devices or subnets. Partial discovery is usually run in response to individual device changes: it can be run on demand, or scheduled for particularly volatile sections of the network. The main purpose of partial discovery is to quickly update topology data for a given device or devices and device connectivity is usually less of a priority when performing partial discovery. Device connectivity can be updated when the next scheduled full discovery is performed.

   Typically you do not need to change any settings on the Advanced tab. However, it is worth noting the following settings:

   Enable Ping Verification

   This setting forces discovery to create network objects only for devices that respond to a ping.

   Enable VLAN modelling

   If you do not need to model VLANs, then disable this option to speed up discovery.

   Enable ifName/ifDescr Interface Naming

   Changes the default naming convention for discovered interfaces. If you change the default naming convention for discovered interfaces, you must change the BuildInterfaceName stitcher to specify your naming convention.

   Discovery stitchers are pieces of code written in Network Manager's proprietary stitcher language that perform two main tasks within the discovery process:

   Data collection stitchers

   These stitchers move data collected from network devices from one database to another. These are system stitchers and are not available for customization by users.

   Data processing stitchers

   These stitchers 'stitch' together the data gathered by the discovery agents to generate the network topology, which can then be visualized and polled. Advanced users can modify these stitchers so that the discovery process will produce a custom topology. For example, as stated above, you can modify the BuildInterfaceName stitcher to specify a custom interface naming convention.

5. Click Save to save your discovery configuration settings.